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131.
Histamine poisoning (scombroid food poisoning) is a toxicity syndrome that results from eating spoiled fish. To date, however, few poisoning (or mortality) cases have been reported in relation to crab consumption. Here, we describe a very uncommon case in which a 37‐year‐old woman and her 14‐year‐old son ate cooked crabs (Scylla serrata), resulting in the death of the female. Samples of vomitus, food residue, liver tissue, gastric content, intestinal content, and cardiac blood were analyzed by high‐performance liquid chromatography. Toxicological analysis revealed that histamine concentrations were very high in the cooked crab (47.08 mg/100 g) and intestinal content (22.54 mg/100 g). Comparing our toxicological results, police investigations, and family member statements, it can be assumed that the decedent ingested spoiled crabs, and by excluding other causes of death, lethal intoxication with histamine poisoning was confirmed.  相似文献   
132.
大鼠死后心血吗啡浓度变化的HPLC检测   总被引:1,自引:0,他引:1  
采用高效液相邑谱分析技术(HPLC)检测治疗量及中毒量吗啡肌注大鼠死后心血中吗啡浓度变化。结果表明,以治疗量吗啡肌往大鼠,在死后96h内,心血中吗啡浓度随死后时间增加而显著升高(P<0.01),吗啡浓度水平与死后时间里显著正相关;以中毒量吗啡肌注大鼠,在死后12h内,心血吗啡浓度无明显变化;死后24h、48h及96h,随死后时间延长,心血中吗啡浓度逐渐升高(P>0.01),其递增强度不如治疗量吗啡组大鼠的明显.本研究证实,死后尸体心血吗啡浓度明显受生前剂量的影响,且在死后96h内,随死后时间增加.心血中吗啡浓度少数不断增高。  相似文献   
133.
本文从小颗粒悬浮液的显现原理出发,选择二硫化钼作为显现物质,对小颗粒法显现手印的试剂浓度、操作方法、对陈旧手印的适用性及小颗粒悬浮液的放置时间进行了研究和探讨,并给出相应的结论。  相似文献   
134.
Abstract:  An evaluation of eight compounds for use as an internal standard in fire debris analysis was conducted. Tests were conducted on tetrachloroethylene, chlorobenzene, n-octylbenzene, 3-phenyltolune, and deuterated compounds toluene-d8, styrene-d8, naphthalene-d8, and diphenyl-d10 to measure the extraction efficiency of each compound in the presence of an interfering volatile compound (carbon disulfide). Other tests were conducted to evaluate whether or not the presence of an ignitable liquid or pyrolysis/combustion products from fire debris would interfere with the identification of these compounds when used as an internal standard. The results showed that while any of the eight compounds could be used as an internal standard in fire debris analysis, the more volatile compounds (toluene-d8, tetrachloroethylene, chlorobenzene, and styrene-d8) showed better extraction efficiencies at room temperature than when heated to 60°C. Each of the less volatile compounds (naphthalene-d8, diphenyl-d10, n-octylbenzene, and 3-phenyltolune) performed well during extraction at 60°C, while naphthalene-d8 showed better extraction efficiency in the presence of competing volatiles when extracted at room temperature.  相似文献   
135.
Abstract: Enzyme‐linked immunosorbent assay (ELISA) and liquid chromatography tandem mass spectrometry (LC/MS/MS) were used to detect diazepam exposure in skeletal tissues of rats (n = 15) given diazepam acutely (20 mg/kg, i.p.), and killed at various times postdose. Marrow, epiphyseal, and diaphyseal bone were isolated from extracted femora. Bone was cleaned, ground, and incubated in methanol. Marrow underwent ultrasonic homogenization. Extracts and homogenates were diluted in phosphate buffer, and then underwent solid‐phase extraction and ELISA. Relative sensitivity of detection was examined in terms of relative decrease in absorbance (ELISA) and binary classification sensitivity (ELISA and LC/MS/MS). Overall, the data showed differences in relative sensitivity of detection of diazepam exposure in different tissue types (marrow > epiphyseal bone > diaphyseal bone), which is suggestive of heterogenous distribution in these tissues, and a decreasing sensitivity with increasing dose‐death interval. Thus, the tissue type sampled and dose‐death interval may contribute to the probability of detection of diazepam exposure in skeletal tissues.  相似文献   
136.
Abstract:  Thiodicarb is a nonsystemic carbamate insecticide whose acetylcholinesterase activity is related to its main methomyl degradation product. A 40-year-old woman was found dead in her car. Empty packages of medicines and an open bottle of Larvin® containing thiodicarb were found near her body. No signs of violence nor traumatic injuries were noticed upon autopsy, and police investigations strongly suggested a suicide. Systematic toxicological analysis performed on postmortem specimens revealed the presence of various sedatives, hypnotics, and antipsychotic drugs in blood, urine, and gastric content. Some of the compounds identified were determined at blood concentrations well above the known therapeutic concentrations: zolpidem (2.87 mg/L), bromazepam (2.39 mg/L), nordazepam (4.21 mg/L), and levopremazine (0.64 mg/L). Specific analysis of thiodicarb and of its methomyl metabolite was then performed on all fluids and tissues collected during autopsy by liquid chromatography ion trap tandem mass spectrometry (LC-MS-MS). The anticholinesterase capacity of blood, urine, and gastric content collected at autopsy was 83%, 82%, and 32%, respectively (normal value: 0%). The presence of thiodicarb in the bottle found near the body corroborates the hypothesis of an intake of that compound. Although thiodicarb was only detected in gastric content (24.3 mg/L), its methomyl metabolite was quantified in most postmortem tissues and fluids: gastric content (19.9 mg/L), peripheral blood (0.7 mg/L), urine (8.5 mg/L), bile (2.7 mg/L), liver (0.7 mg/kg), kidney (1.7 mg/kg), lung (1.5 mg/kg), brain (9.3 mg/kg), and heart (3.6 mg/kg).  相似文献   
137.
Abstract: A case is presented of a 39‐year‐old woman who suffered severe debilitation because of a hemorrhagic stroke in the context of substance abuse. The patient presented to the emergency room with rapidly diminishing mental status, hypertension, and vasoconstriction; her friends provided a history of ingestion of cocaine, 3,4‐methylenedioxymethamphetamine (MDMA), and 2C‐I, a novel designer amine. A multi‐targeted LC‐MS/MS method for sympathomimetic amines and related drugs in urine detected and quantified 2C‐I and MDA, while ruling out MDMA. The cause of the stroke was determined to be an underlying cerebrovascular abnormality called Moyamoya, secondary to substance abuse. In clinical laboratories, gas chromatography–mass spectrometry or liquid chromatography–tandem mass spectrometry (LC‐MS/MS) confirmation of a positive amphetamine immunoassay is usually directed only towards amphetamine, methamphetamine, MDMA and MDA. This report demonstrates the utility of testing for a wider menu of compounds using LC‐MS/MS in order to better characterize the prevalence and toxicities of novel amines such as 2C‐I.  相似文献   
138.
LC-MS/MS同时测定人血浆中氯氮平、奥氮平和米氮平   总被引:2,自引:0,他引:2  
目的 建立人血浆中氯氮平、奥氮平、米氮平的液相色谱-串联质谱(LC-MS/MS)检测方法.方法 血浆中的氯氮平、奥氮平、米氮平用乙醚液-液萃取,采用Agilent Zorbax SB-C18柱(2.1mm×l50mm,5 μm),电喷雾离子源,正离子检测,多反应监测方式进行定量分析,卡马西平作为内标.结果 氯氮平、奥氮平和米氮平的检测限为0.41~0.92ng/mL,质量浓度在10.0~2000.0ng/mL范围内线性良好(r≥0.9924),平均萃取回收率在65.7%~94.2%,日内、日间精密度RSD≤6%(n=5).结论 该方法专属性强、灵敏及准确,可以适用于法庭与临床毒物分析.  相似文献   
139.
HPLC法测定百草枯急性中毒大鼠的体内分布   总被引:2,自引:1,他引:1  
目的 应用高效液相色谱法对口服百草枯急性中毒大鼠体内分布进行测定。方法以200mg/kg剂量百草枯给予Wister大鼠灌胃,4h后脱臼处死,解剖取脑、心、肝、脾、肺、肾、胃、盲肠、肌肉等组织,应用固相萃取法提取,液相色谱法测定各器官组织中百草枯含量。结果各组织经检验,均检出百草枯;组织间百草枯含量(μg/g)相差明显,其中最高为胃(231.47±129.10),其次为盲肠(87.08±39.86)、肺(22.73±10.20),最低为心(2.01±0.36)。结论百草枯口服给药后组织分布较为广泛,除胃、肠外各脏器中以肺浓度最高。  相似文献   
140.
目的建立苯二氮卓类新精神活性物质去氯依替唑仑的气相色谱-质谱(GC-MS)和超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF MS)定性检验方法。方法未知样品用甲醇和水提取,取上清液,采用GC-MS和UPLC-Q-TOF MS进行分析。结果经GC-MS检测,保留时间为17.73 min的未知组分的质谱碎片主要特征离子峰有m/z 279,308,239,252,225,77,126。经UPLC-Q-TOF MS检测,保留时间为4.781 min的未知组分的准分子离子峰为309.1173,碰撞诱导解离(CID)模式下二级质谱主要离子有m/z 280.0776,255.0952,240.0719,225.0604,206.0748。经缴获毒品分析科学工作组(Scientific Working Group for the Analysis of Seized Drugs,SWGDRUG)分析谱库检索和文献查询获得的信息资料进行比对,鉴定为去氯依替唑仑。结论该方法具有分析简便、快速的特点,可以用于实际案件的检测。  相似文献   
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